Using Light Interception and in-Situ Surface Reflectance in Support of Moderate Resolution Remotely Sensed Phenology

Time series of vegetation indices derived from remote sensing are increasingly being used to monitor vegetation phenology. However, a variety of factors confound interpretation of remote sensing results. To more fully exploit the power of remote sensing and to improve its utility for studies of landscape-to-regional scale phenology, more and better in-situ information is required for both calibration and validation purposes. In this paper, we present results from analyses of field data collected over the 2006 and 2007 growing season at Harvard Forest that use light interception and surface reflectance measurements to monitor canopy development. As part of this analysis we compare these high temporal measurements against 8-day composites of the enhanced vegetation index derived from the Moderate Resolution Imaging Sepctroradiometer. The goal of this study is to provide a proof-of- concept for future studies that include more spatially extensive and temporally continuous measurements related to canopy development. In the near future we hope to extend this study to include three additional forested sites in New England, thereby providing a transect that includes a gradient in climate and forest types.